1. Field of the Invention
The present invention relates to product valves for filling machines. Specifically, the present invention relates to a product valves for a dual stream filing system for a filling machine.
2. Description of the Related Art
Packages formed from a blank are usually processed on a linear form, fill and seal packaging machine. Each blank is delivered to a mandrel of the packaging machine from a carton blank opener. The blank opener is fed with a series of blanks from a magazine. The magazine holds a stack of flat blanks that are erected on the carton blank opener prior to placement on the mandrel.
Once on the mandrel, each carton has its bottom formed prior to placement on a conveyor. On the conveyor, each carton may be fitted with a fitment and sterilized prior to filling and top sealing. Novel filling techniques as disclosed in U.S. Pat. No. 5,687,779 have emerged to fulfill a need in the packaging industry, that need being the ability of a packaging machine to consecutively fill cartons with different products. This breakthrough in the packaging industry has created additional problems that must be met before the full potential of the novel filling systems is realized by dairies and other producers of flowable food products such as milk, juice, yogurt and the like.
One of the most pressing needs is the ability to fill a single product on a dual stream filling system, especially the secondary product which may be metered at a much slower rate than the primary product. There is also a need to accomplish this single product filling without making major modifications to the dual stream filing system.